Ugh...My 400's Engine


5 replies to this topic
  • Markopolo400

Posted April 10, 2007 - 10:30 AM

#1

Well...I think the pictures speak for themselves...Kinda.

My 400 is getting completely rebuilt after it started making a funny tinking sound...

Everything is getting replace in the valve train, along with the piston, and the cam chain.

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Is all the wear on the exhaust cam normal?
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Man I wish I had a 250 smoker right about now...Haha.

  • dwnlowx

Posted April 10, 2007 - 11:23 AM

#2

wow did you find your problem

  • Markopolo400

Posted April 10, 2007 - 02:32 PM

#3

Not sure exactly what it was yet...Hoping that it was either the cam chain, or the valves.

The ex valves were super tight when I took it apart, and I'm hoping that's what it was. If it's not I don't know what I'll do. :thumbsup:

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  • Birdy426

Posted April 10, 2007 - 03:22 PM

#4

Check the primary drive nut...they have been known to come loose...

  • TD-3

Posted April 10, 2007 - 05:42 PM

#5

The exhaust cam journal closest to the gear looks completely worn out :thumbsup:
I would guess that is why your valves clearance was tight.

  • grayracer513

Posted April 10, 2007 - 06:13 PM

#6

The exhaust cam journal closest to the gear looks completely worn out :worthy:
I would guess that is why your valves clearance was tight.

If you are speaking of the area between the sprocket and ball bearing on the one side, and the cam lobe on the other, that isn't a cam journal. It's just the shaft. Nothing runs against it. :thumbsup:





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